Pumping mechanism



May 31, 1949.y Dgp, DAVls :2,471,939

PUMPING MECHANI SM Filed Aug. 18, 1944 2 Sheets-Sheet 1 May 31, 1949. v D. P. DAVIS 2,471,939

PUMPING MECHANISM Filed Aug.` 18, 1944 v 2`sheets-sheet 2 Patented May 31, e 1949 airmail t JMIMruilen;MFQHAMSM `rpenglas'?,flgayisurbank, Calif. Applicatin Augustus, 1944;,seria1 No, 550,050 "giornale, (c1. 10s- 174) Pliner; `.means beinei ;S maylfbe iliade :toi Qpgrat they arenequired withcut varying-tithe, Speed fof rctaticntoi;theudrvingtshaftl.

Anotheiianimare;specificpbiectfottheziuvcntionolisitclptoyide aipumpimech miempleyillg a.: plurality. of reciprocatinelpistcns .avneia 9011- necting rod assembly,including;arr-anmHuSQDerwithinmtheannulusrand coupled sinialmvehmannerartwith tatdrivingl, crankgshait: continuously Jrotatingfaticonstantspeed;whereby:uponctheifshif-ting` oft-the connecting` .rod assembly thetdisk,

previously A, concentric.,...withx .the ishaft, .,twilll ibe: 25A

shifted to an eccentricposition withrespectlthereto to set up necessary eccentric `rotationtoitthe annulus and. consequent actuation voiethe pump pistons connected therewithl A r lThe invention will` be tbest understoodl ffrom ai consideration wofthey following '-detailed description taken in association withA thea'onbanyingdrawings -forming a l part ofthel spci'ii'cation Withlthe understanding that changesnnajy` inthel structure illustrated and l described s aswsuch changesv are within "thescpe/ofrthe appendedclaimsL In thedrawings:

Figure l is av View in crossglsectiono/ f' aj conventionally illustrated, constructedi ancewith fthe `present"inveriltin.

myFigure Zyis a section jtaken on jthel ine 2f"'`2 olFigurel. 'a

@Figure 5jis a view illustratinggjthe 'eccentric"z m vie' tien is illustrated,` tl'le numeral .l designates inner and outer ends bythe pinsa limitiert, 5.5 tris:

l the diskand house being sectioned substantially ontlie line 545 l'of Figure '7.

`,figure l is a section tairensubstantiallynon theiine i-i of Figure 6.

Figure 8 is a detail View illustrating-another embodiment of the spring control ior tlvedisfklM 'Eigure 9. isha sectional view 'i'ialzeny substantially LReferring now incre` particularly :to the ,draw- Awherein 'the preferred embodiment of the inafj uwer liar/'inge as` yanintegralpart k1tlfe`r-ehof ank` il which comprises vthe'twp spaced parallei' `radial arnis i2A whirclfiare` coinjiected)aty their andi Merespectivelyl i having one `end adjacent thewcenter-oitlie.idisk e 30 pinsis such thatwhen the pin isl at thelenter ofthe disk` I5 the othery pinwillbbe aty-thelguter endof the ,slot H, which isthe lend iarthestgirpm the' center ofthe disk.

t `Within the slot ll ,there is 4 disposed,angempression spring i8, which isl interpgsedsbetween thepin it andthe innerend ofltheieccentric slot. This .spring constantly i urges moyernentlioi-the pinlfl't to the outer endof thefecentricL-s'lot and consequentlyeffects the shiitingof'the'cente lpin l'fltoY the `center' of the disk i'sotl'iatthewgisk willfi,nornially` turn concentric lwithQtlie shaft.

' Encircling the disk `l5"is a connecting 1309i., assembly consisting of an annular strap; `I9 nd a number of `radial armsiconnetflftcIthu;ny ltside thereof; One of these arns iswrelativelylong asindicated at.; 26 and forms adpistonrod i alpurnp 2l while the other arms are vshortfa cated at `22 and are,pivotallylconneeted; `uitagblewwrist pins 23 withpisto rs'zt f umps 25.,"The pumps are equidistantlylspace the" eccentric strap as illustratedan three pumps are shown it is tjjbe undk ood that any number, two or mre,'n1a `be mw eyed, d'esiredgspaced evenlyargundfthew cylinders or from the pumping mechanism as a whole. The several cylinders of the pumping mechanism may be supplied by the pipe 26 through a supply or intake manifold 28 while the lead-off pipe 26 may be similarly connected to an exhaust or outlet manifold 29.

The several cylinders of the pump are supplied from the intake manifold 28 through the inlet valve controlled ports 3U and similar outlet valve controlled ports 3| lead from the cylinders to the lead-off or exhaust manifold 29.

Connecting across between the feed or supply pipe 26 and the exhaust pipe 26' is a cross over pipe 2l in which is a shut-off Valve 2.

In addition to the shut-01T valve 21' there is provided a flow control or restrictor valve 32 which is located in the lead-olf pipe 2S and past which must flow the fluid pumped out through the exhaust manifold.

The operation of the pumping mechanism described is as follows:

It is obvious that if the disk I5 is turned about its axial center as indicated in Figure l, with the outer crank pin I4 at its farthest position from the disk center and the inner pin i3 at the center of the disk, the disk will turn freely within thev annulus of the connecting rod assembly and no motion would be transmitted to the piston rods and the pistons connected therewith. This would be the idling phase of the pump mechanism operation.

To get the pump started so as to effect the movement of the fluid through the pipe line connected with each pump cylinder, the valve 21 would first be closed. A force would then be applied to a piston or the connecting rod assembly in a line radial to the line of rotation to tend to push the piston assembly off center. The force would be suiiicient to cause the spring in the slot l'l to be compressed so as to move the disk across the rotary axis of the shaft and with relation to the two crank pins when the disk rotates to the proper position. This relative motion moves the center of the disk away from the axis of rotation and causes the periphery of the disk to turn eccentrically about the :axis of rotation of the shaft. Such eccentric motion of the disk causes a corresponding eccentric movement or rotation of the annulus or the connecting rod assembly and effects the desired reciprocation of the piston rods.

The disk will remain in an eccentric position with respect to the crank shaft as long as the spring in the slot remains compressed. This condition will prevail as long as there is resistance to motion of the pistons, as in pumping against a pressure head.

`As previously stated the restrictor valve 32 is provided to assure a denite minimum pressure against the discharge of the pump.

To explain more specifically the manner of putting the pump into pumping operation take for an instantaneous example the case where the members are in the positions shown in Figure 1 when the disk and shaft are rotating. The crank shaft is supported in bearings and therefore cannot be moved by any radial force. Under these conditions, if a force were applied to the upper piston 2l, there could be no lateral or downward movement of the disk because Ythe not critical.

4 left hand pin, the crank pin I4, is at the outer end of the eccentric slit I1'. If it be supposed that a force were applied toward the center of rotation on the piston at the lower left of the figure mentioned, there still would be no motion of the disk, because the crank pins I3 and ill are at the ends of their respective slots and will not let the disk be moved. If, now, it be supposed that a force is applied to the lower right piston, such force would displace the disk by compressing the spring as the disk could be shifted, together with the annulus and the connecting rods attached thereto, into the position in which it is shown in Figure 3. The disk would then automatically be given eccentric motion and such eccentric motion would be imparted to the whole assembly.

As previously stated the rst operation in starting the pump is to shut the communicating valve 2l between the pipes 26 and 26. Thus the ow of liquid between the pipes 26 and 26 is shut off and such liquid must pass from the pipe 26 into the intake manifold 23 to supply the pump cylinders. When this is done, any eccentric motion of the piston assembly starts the Apumping action and hence offers resistance to the rotational movement of the crankshaft. Any resistance of this kind keeps the spring compressed and hence keeps the disk in its eccentric position.

n the above instantaneous example, the description of the application of force to first one and then the other of the pistons has assumed the disk to be motionless although it is one of the novel features of the present mechanism that the disk turns constantly. To proceed further, if a force is applied to any of the pistons or to the rod or disk in any manner whatsoever, as

long as it is a radial force, as the disk turns aboutv its center of rotation, it will reach a position in each revolution where the force can move the disk and whole assembly into the eccentric position as previously explained in connection with the above reference to Figure 3. Once the assembly has been moved into this position slightly,` the pumping load will offer sufficient force to completely compress the spring.

The manner of applying the load or force is It could be applied by introducing uid into one pump cylinder under suilicient pressure or it could be applied by some mechanical means.

As an illustration of one mechanical means of applying the desired force to the connecting rod assembly there ls shown a plunger rod 33 mounted for reciprocal movement through the wall of the pump crankcase. This plunger is free to be pushed in against the annulus of l of the connecting rod assembly, by hand or any In this arrangement the shaft is designated lll'l and at one side the crank is of tubular form as indicated yat 35. Extending through this tubular portion 35 of the crankshaft is the pin I3 whichr is unconnected with the shaft and, at its inner end is of s quare or rectangular cross section, instead of being round as in the portion which passes rI-he shaft is here illustrated ashaving one side tb`1i1ar`to"receivetheA crankshaft pin I3, the inneren'd f 'which is s'iuard as'illiistratedin connectioif` with lthe' pin "`I 3 tt'a'chedto one u'side face of the disk l5" by means of the vrigid-connection 36, is a leaf spring 3l which extends outwardly across the arcuate slet "l1","the'norm`al rlunflexed position of the free outer end being adjacentftoiftheruter end of the arcuatefslot. *f-Between'the outer` end of the arcuate slot and the free outer end of the leaf springWSLthe crankpin I4 'is `located during the p'eriodbf'dling operation of the pump or, in other wordafwhenthe' disk is 'turning' concentrically with the crankshaft "It is`"beli`e`ved"to `be 'readily obvious thatthe pp'rationof the pumpusingfthe leaf typespring 31A" would `be 'the' same as'inusi'ng the coil type spring l8"shown" in Figures 1,` 3 and 5, therefore, a""dtailed "description of the operation of the mahirie'iisingithis'specic forn'iof' spring isbelieved to be unnecessary.

When it is desired to stop the pump, the valve 21 is opened. This connects the inlet of the pump to the outlet and eliminates back pressure against the discharge. This action eliminates the eccentric force previously applied against the connecting rod assembly, which lets the spring in the slot move the disk back to the position shown in Figure 5, where the periphery of the disk rotates concentrically about the axis of rotation of the crankshaft.

I claim:

1. A pumping structure comprising a pump including a piston, a disk having a slot extending from adjacent the disk center and an eccentric arcuate slot, a shaft, a crank carried by the shaft and having two pins each passing through a slot, one pin being concentric with the shaft and pass-- ing through the first slot, the pins being so spaced that when the said one pin is in the center of the disk the other pin is in the outer end of the arcuate slot, an annulus on and encircling the disk, and a driving coupling between the annulus and the piston.

2. A pumping structure as set forth in claim 1, including a valve controlled inlet for the pump, a valve controlled outlet for the pump, and a valved coupling between the inlet and outlet and by-passing the pump.

3. A pumping structure, comprising a shaft, a disk disposed in a plane perpendicular to the shaft, a member concentric with the shaft and connected with the disk for movement relative to the disk from the center of the disk a predetermined distance radially, a second member carried by and eccentric to the shaft and having eccentric 6 connection with the1disksnd-inovb1ereiativeifte thefdisk in' an arcuate patlffeccentric thereto'mid directed across thepath `frnovernent ofthrst member, s'aidmembers forming'aV driving connection-betweenthe shaft and the diskwhereby the disk may be selectivelyl rotatdconcentrictvith the shaftf'or eccentric "thereto,` resilientineansrirmany urging movement oftheidiskreiative-tdtne shaft =to"a^`pos`ition lii/here' the vldisk will "be rotated concentric"with` the shaft,"purnp" units arranged around thev periphery of theuisirand eaoii'iricldding a cylinder having'n"intake"and'outlet'e.nd a'piston, an" `annulus carried by and encircling'the diskan'din which theitiisk turns; a"dri'ving"'con nection between the' pistons ""and "the annulus, means for 'shifting the disk 'to saideccentriciposition "against the resistance of said ""resili'ent means, and means" for" "maintaining" 'the `"dis`k' in said 'eccentric position.

4. "A purmii'igv 'structure' asset 'forthin "clainiv 3, 'in whi'ch'said members are in the form'of crankpins and in which the connections-between"the memloe'rs`v and the "disk comprise slots in 'which the pinsA slidablyf engage.

"75. A 'pumping s'tru'ctu're asf'set forth in".c1m 3, jin" which" the members 'connecting' 'the"`ishaft with 'the-disk' 'are in the form"`of"'cra`n'kpins arid inf which `the connections' between" the"members and `the diskv comprise 'sl'ots ""in-J which the "pins slidably engage; v"and isaid resilfe'ntfmeans`com prises' a coil spring lying in"the"slot"'in" which the second'4 mentioned pinfmei'nber moves.

6. Ay pumpingstructurerfasf'set fortlfi` hr cla'in 3, in-whioh-thef members `'connecting' thefsrrart'n with the disk are 'in the form" of cra'rikpins and 'in'fwhich the connectionsbetweerr theimemlbers r`andiitlie diskicmpriseislbts iniwhch thel'pins slid'aibly engage. and -sa-id-resilientfmeans comprisesfa'fleaf springfseeuredfatone y'e`.`r'`1d`-to-'the Vdisk andih'afving a free end extending across the slot in which the second mentioned pin member slidably moves.

7. A pumping structure as set forth in claim 3, in which the said means for shifting the disk to the eccentric position comprises a pin supported for movement against the periphery of the annulus for applying radial pressure against the disk.

8. A pumping structure as set forth in claim 3, in which the said means for shifting the disk to the eccentric position includes the first mentioned member which is so constructed and arranged that a braking force may be applied to the disk to retard the rotation thereof.

9. A pumping structure as set forth in claim 3, with a valved passage connecting the intake and outlet of the cylinder, and a flow restrictor valve connected with the cylinder outlet for imposing a back pressure upon iiuid flowing therefrom.

10. A pumping structure comprising a pump including a piston, a disk, a shaft connected with the disk to rotate the same, means for shifting the disk transversely of the shaft between positions concentric with and eccentric to the shaft, and an operative driving connection between the disk and the piston, the connection between the disk and shaft comprising a crank having a pin concentric with the shaft and a pin eccentric with the shaft, the pins passing through the disk.

l1. A pumping structure, comprising a shiftably supported continuously rotating circular member, at least two lpiston cylinders equidistantly spaced around the periphery of the member, pistons in the cylinders, a valve controlled inlet and a valve controlled outlet for each cylinder, means forming a driving 'connection between the periphery of the member and the pistons which is so constructed and arranged that the member when shifted to one position rotates in the center of the space between the cylinders without driving the pistons and when shifted to another position rotates eccentrically in said space to drive the pistons, means for maintaining the member in said eccentric position, means in circuit with the outlet for maintaining a back pressure against iiuid leaving the cylinder, and the penultimate means being designed to be maintained operative by reason of such back pressure. k

12. A pumping structure comprising a shaft, a disk disposed across the shaft, a continuous driving connection between the shaft and disk which is so constructed and arranged that the disk may be shifted from a position concentric with the shaft to a position eccentric thereto, pump units arranged around the periphery of the disk and each including a cylinder having an intakeand an outlet and a piston, an annulus carried by and encircling the disk and in which the disk turns, a driving connection between the pistons' and the annulus, means for shifting the disk to the eccentric position, and means for maintaining the disk in said eccentric position, said last means comprising a valved by-pass connection between said cylinder inlet and outlet.

13. A pumping structure comprising a pump including a piston, a disk, a shaft connected with the disk to rotate the same, means for shifting the disk transversely of the shaft between positions concentric with and eccentric to the shaft, and an operative driving connection between the disk and the piston, the said driving connection being at the periphery of the disk.

14. A pumping structure, comprising a shiftably supported continuously rotating circular member, at least two piston cylinders equidistantly spaced around the periphery of the' member, pistons in the cylinders, means forming a driving connection between the periphery of the member and the pistons which is so constructed and arranged that the member when shifted to one position rotates in the center of the space between the cylinders without driving the pistons and when shifted to another position rotates eccentrically in said space to drive the pistons, means for effecting the shifting of the circular member from concentric to eccentric position during rotation of the member, means for maintaining the member in said eccentric position, the said last means being kept effective so long as resistance is maintained to the movement of the pistons inwardly in their respective cylinders, and means for effecting the shifting of the circular member back to the said one position where it rotates in the center of the space between the cylinders without driving the pistons when the said resistance to the movement of the pistons into their respective cylinders is removed.

DOUGLAS P. DAVIS.

REFERENCES CITED The following references are of record in the le of this patent:

UNETED STATES PATENTS Nun'iber Name Date 1,040,057 Tokneim Oct. 1, 1912 1,149,728 Ciarlo Aug. 10, 1915 1,477,300 Thrift Dec. 11, 1923 1,630,168 Caut May 24, 1927 1,633,720 Wilsey June 28, 1927 1,982,958 Kraus Dec. 4, 1934 2,203,646 Aspden June 4, 1940 2,268,695 Carlson Jan. 6, 1942 2,406,115 Stephan Aug. 20, 1946 

